Solenoid valve with improved damping, and method for producing same

Abstract

The invention relates to a solenoid valve comprising a first connection (1), a second connection (2), an armature (5) and a coil (6) for moving the armature (5). The solenoid valve comprises: a first closure part (7a) which is coupled to the armature (5) and opens or closes the first connection (1) as a result of a movement of the armature (5); a second closure part (7b) which is coupled to the armature (5) and opens or closes the second connection (2) as a result of the movement of the armature (5); and a damping spring (8) which is arranged between the first closure part (7a) and the second closure part (7b ) and is designed to dampen the closing process of the first connection (1) and / or the second connection (2).

Description

[0001] DESCRIPTION

[0002] Solenoid valve with improved damping and method for its manufacture

[0003] The present invention relates to a solenoid valve with improved damping and a method for its manufacture and, in particular, to a 2 / 3-way valve with double damping.

[0004] Solenoid valves are used, for example, as 2 / 3-way valves for pressure control of anti-lock braking systems (ABS) or traction control systems (ASR) in commercial vehicles or buses. These solenoid valves are subject to intensive use during operation and must function reliably over many actuations.

[0005] However, due to the high stress they are subjected to, conventional solenoid valves show significant wear over time, meaning that reliable switching (opening and / or closing) is no longer possible or only inadequately possible. In particular, the sudden switching processes and the resulting high forces, which are caused, among other things, by pressure differences, often lead to mechanical wear on the valve seats and / or the closing components. This wear can be further exacerbated by the air routing, i.e., the redirection of the air flows within the valve. With conventional valves, it has been shown that the components used are often unable to withstand the strong air flows over the long term.

[0006] Therefore, there is a need for alternative designs for solenoid valves that, on the one hand, enable simple manufacturing and, on the other hand, can ensure reliable operation throughout their entire service life.

[0007] At least some of the above-mentioned problems are solved by a solenoid valve according to claim 1 and a manufacturing method according to claim 9. The dependent claims define further advantageous embodiments of the subject matter of the independent claims. The present invention relates to a solenoid valve having a first port, a second port, an armature, and a coil for moving the armature. The solenoid valve further comprises a first closure member, a second closure member, and a damping spring. The first closure member couples to the armature and opens or closes the first port upon movement of the armature. The second closure member couples to the armature and closes or opens the second port upon movement of the armature. The damping spring is arranged between the first closure member and the second closure member and is designed to cushion or dampen the closing of the first port and / or the second port.

[0008] The first closure part and the second closure part can be designed as sealing pills that reliably seal the corresponding valve seats. They can be flat or tapered to achieve a good seal. The direction of movement of the armature defines an axial direction.

[0009] Optionally, only a damping spring is arranged between the first and second locking parts, which pushes the first and second locking parts away from each other. They can thus be preloaded.

[0010] The first closure part can also be identical in design to the second closure part. This offers the advantage that only one type of closure part needs to be manufactured. After insertion, the two closure parts are only rotated 180° relative to each other. This enables simple and cost-effective production.

[0011] Optionally, the solenoid valve comprises a third port and a chamber in which the armature can move linearly together with the first and second closure parts. The first, second and third ports can provide a connection to the chamber (e.g. via external port parts). When the coil is energized, the first closure part can close the first port and the second closure part can establish a fluid connection via the chamber between the second port and the third port. When the coil is de-energized, the second closure part can close the second port and the first closure part can establish a fluid connection via the chamber between the first port and the third port. In this way, the solenoid valve becomes a 3 / 2-way solenoid valve.

[0012] Optionally, the armature extends cylindrically around the first closure part and around the second closure part and comprises a section that protrudes axially beyond the first closure part. In addition, the armature can have a longitudinal side channel (e.g., a groove). The armature can then have at least two through-openings between an inner region of the armature and the side channel, of which (at least) a first through-opening is formed in the protruding section and (at least) a second through-opening is formed in a region of the armature that lies axially between the first closure part and the second closure part, in order to provide pressure equalization between the inner region and an outer region (e.g., the third connection) of the cylindrical armature. Optionally, a plurality of first through-openings and / or a plurality of second through-openings can also be formed in order to better distribute the air flow.

[0013] Optionally, the at least two through holes are designed as identical bores. "Identical" in turn means that they can be produced using the same tool (e.g., drill) and therefore do not differ—apart from their position. Alternatively or in addition to the through holes, the armature can also have slots or cutouts through which the air flow can pass.

[0014] Optionally, the first closure part and / or the second closure part each comprise a head-shoulder region for closing the associated first or second connections. The armature can have a projection projecting radially into the interior and / or, at an opposite end, an annular recess with a stop element. The projection can be configured to form a stop for the head-shoulder region of the first closure part. After insertion of the first closure part, the damping spring, and the second closure part, the recess can fix the second closure part in the axial direction by means of the stop element.

[0015] Optionally, the stop element is a disc, which can be secured within the recess by compressing the edge of the anchor. However, it does not have to be a continuous disc. It is sufficient to form an axial stop for the second locking part. However, it should not be completely fixed.

[0016] Embodiments also relate to a method for manufacturing one of the solenoid valves as described above, which thus have at least a first connection, a second connection, an armature with a cylindrical interior, and a coil for moving the armature. The method comprises:

[0017] - Inserting a first closure part into the interior of the anchor;

[0018] - Inserting a damping spring into the interior of the armature; and

[0019] - Inserting a second closure part into the interior of the armature, wherein the first closure part and the second closure part are designed to alternately open or close the first connection or the second connection upon movement of the armature, while the damping spring provides damping upon closing of the first connection and / or the second connection.

[0020] Optionally, the method also includes forming a stop for the second closure part by compressing the edge of the armature. This fixes the first closure part, the second closure part, and the damping spring arranged therebetween within the cylindrical cavity of the armature with respect to their maximum separation.

[0021] It is understood that all of the previously described features of the solenoid valve can be implemented through additional optional process steps. Furthermore, it is understood that the order in which the steps are listed does not necessarily reflect the order in which the process steps are executed. The steps can also be performed in a different order, or only some of the process steps are performed.

[0022] Embodiments of the present invention overcome the problems mentioned above by using (only) one spring that dampens the impact of both closure parts on the valve seats. This is made possible, for example, by closing both ports on opposite sides, which can be dampened by means of the simple compression spring.

[0023] Some designs offer the advantage that double damping significantly increases the service life of the solenoid valve. Less damage occurs, and opening and closing occur with high precision. Therefore, the solenoid valves are suitable for applications requiring a high number of switching operations, such as those required for ABS solenoid valves.

[0024] A further advantage of these embodiments is that both closure parts can have the same design and can thus be manufactured interchangeably. This significantly simplifies and reduces the cost of production. Cost savings are also achieved by requiring fewer parts due to the dual damping.

[0025] The same applies to the formation of the through-holes, which can be formed by similar bores, since both the through-hole in the central area between the two closure parts and in the upper end area can be produced in a single work step using the same tool. According to exemplary embodiments, the outer groove along the anchor can already be present in the precursor material (rod material), which also shortens the manufacturing process and production time.

[0026] The embodiments of the present invention will be better understood from the following detailed description and the accompanying drawings of the various embodiments, which, however, should not be construed to limit the disclosure to the specific embodiments, but are for explanation and understanding only.

[0027] Fig. 1 shows a solenoid valve according to an embodiment of the present invention.

[0028] Fig. 2 shows a schematic flow diagram for a manufacturing method for a solenoid valve from Fig. 1 .

[0029] Fig. 1 shows a solenoid valve with improved damping according to an embodiment of the present invention. The valve shown is a 3 / 2-way valve which can selectively connect three ports to one another by means of two switching positions. For this purpose, the solenoid valve comprises a first port 1, a second port 2, a third port 3, an armature 5, a coil 6, a first and a second closure part 7a, 7b, and a damping spring 8. The coil 6 serves to move the armature 5 (by magnetic forces). The first closure part 7a couples to the armature 5 and opens or closes the first port 1 when the armature 5 is moved by the coil 6. The second closure part 7b also couples to the armature 5 and opens or closes the second port 2 when the coil 6 moves the armature 5. The damping spring 8 is arranged between the first closure part 7a and the second closure part 7b.When the first port 1 and / or the second port 2 are closed, the damping spring 8 absorbs the impact (or impact) on the corresponding valve seat. It thus improves damping and protects the closure parts 7a, 7b and the valve seats on the ports 1, 2.

[0030] The coil 6 can, for example, be housed in a valve body housing 10 and extend cylindrically around a core 4 and the armature 5. The core 4 can, for example, be fixedly arranged within the coil 6 and provide the first connection 1 as a through-opening. The armature 5 is displaceable in the axial direction (vertical in Fig. 1), with a compression spring 11 being present between the core 4 and the armature 5, which generates a preload. The armature 5 can, for example, have a protruding section 5a which projects axially beyond the first closure part 7a and defines a cylindrical inner region in which the compression spring 11 is guided and which receives a valve seat 12 of the first connection 1.

[0031] The first and second closure parts 7a, 7b can move relative to the armature 5 by compressing the damping spring 8. However, this movement is limited axially in both directions by a stop. For this purpose, the first and second closure parts 7a, 7b each comprise a narrowed region 17a, 17b forming a shoulder-head region, with the head portion serving to close the associated first or second opening 1, 2, and the shoulder serving as a stop.

[0032] In addition, the armature 5 comprises a projection 5c projecting radially into the interior, which forms the stop for the shoulder portion 17a of the first closure part 7a. The compression spring 11 can also engage this inner projection 5c and press the armature 5 away from the core 4. At an opposite end, an annular recess 5d is formed in the armature 5. The annular recess 5d, together with the head-shoulder region 17b of the second closure part 7b, is formed in such a way that a disc 9, for example, can be inserted there, which is easily fixed, for example, by compressing the armature 5. Both closure parts 7a, 7b are then fixed in the armature 5 by an axial stop.

[0033] When the coil 6 is de-energized, the compression spring 11 pushes the armature 5 away from the core 4. This causes the first closure part 7a to open the first terminal 1, since the first closure part 7a is moved by the stop 5c. At the same time, the pre-adjusting force of the compression spring 11 is sufficient to move the armature 5 until the armature 5 closes the opposite second terminal 2 through the second closure part 7b. The contact of the second closure part 7b with the second terminal 2 is dampened by the damping spring 8.

[0034] When the coil 6 is energized and a magnetic field is thus generated, the armature 5 is magnetically drawn toward the core 4 against the spring tension of the compression spring 11 until the first closure part 7a closes the first connection 1. When the coil is energized, the armature 5 is magnetically drawn into the coil in the direction of the connection 1. In this case, the stop, via the disc 9, transfers the force from the armature 5 to the second closure part 7b, which transfers the force to the first closure part 7a via the damping spring 8. The pressure force when closing the first connection 1 is thus limited to the spring force of the damping spring 8 and thus protects the solenoid valve.

[0035] As a result of this movement, either the second port 2 or the first port 1 is opened or closed. When the second port 2 is open (energized state), a fluid connection exists between the third port 3 and the second port 2. The third port 3 can be formed in a base section next to the second port 2 in the valve body 10. In this case, no further provisions for air flow between the second and third ports 2, 3 are required.

[0036] Fig. 1 shows only the switching position with the first connection 1 open. To guide the air flow from the first connection 1 into the interior of the valve housing 10, the armature 5 has at least two through-openings 13 and at least one side channel 14 (e.g. formed as a groove). The at least two through-openings 13 connect an interior region of the armature 5 and the side channel 14 and provide a fluid connection between the first connection 1 and the third connection 3. For example, at least one first through-opening 13a is formed in the protruding section 5a and at least one second through-opening 13b is formed in a region 5b of the armature 5 that is located axially between the first closure part 7a and the second closure part 7b. The at least one second through-opening 13b provides pressure equalization between the interior region of the armature 5 and the third connection 3.The second through-opening(s) 13b are located axially at the height of the damping spring 8 and reduce the wear on the first closure part 7a and the second closure part 7b due to the pressure equalization.

[0037] It is understood that multiple through-openings 13 and / or multiple side channels may be provided to distribute the air flows as evenly as possible throughout the interior due to the considerable pressure conditions. The second port 2 and the third port 3 may be formed as through-openings in the valve body housing 10.

[0038] Fig. 2 shows a schematic flow diagram for a method for manufacturing one of the previously described solenoid valves. The method comprises:

[0039] - Inserting S110 a first closure part 7a into the interior of the armature 5;

[0040] - Inserting S120 a damping spring 8 into the interior of the armature 5; and

[0041] - Inserting S130 a second closure part 7b into the interior of the

[0042] Anchors 5.

[0043] The first closure part 7a and the second closure part 7b are designed to alternately open or close the first connection 1 or the second connection 2 upon movement of the armature 5, while the damping spring 8 provides damping upon closing of the first connection 1 and / or the second connection 2.

[0044] Optionally, the method comprises, as a further method step, forming S135 a stop for the second closure part 7b to ensure the fixation of the first closure part 7a, the second closure part 7b, and the damping springs 8 arranged therebetween within the cylindrical cavity of the armature 5. Forming the stop can, for example, involve inserting the disc 9 and compressing the edge of the armature 5. After this, the disc 9 can no longer be removed from the recess without being destroyed.

[0045] It is understood that all of the other features of the solenoid valve described above can be implemented as additional optional manufacturing steps. Furthermore, it is understood that the order in which they are listed does not necessarily represent the order in which the process steps are executed. The steps can also be performed in a different order, or only some of the process steps are performed.

[0046] The assembly and media routing can be summarized as follows: The assembly sequence can therefore be as follows: first, the cylindrical armature 5 is prepared, into which the first closure part 7a is inserted. The first closure part 7a comprises a head region and a shoulder region, wherein the radially inwardly projecting projections 5c of the armature 5 engage in the shoulder region and provide a stop so that the first closure part 7a can only be moved up to the radial projections. The damping spring 8 can then be inserted into the cylindrical armature 5. Finally, the second closure part 7b is placed onto the damping spring 8. Finally, the disk 9 is inserted. Since the second closure part 7b also has a shoulder section and a head section, the disk abuts the shoulder region and thus provides a stop for the second closure part 7b.For this purpose, the armature 5 includes the circumferential recess 5d into which the disc 9 can be inserted. After the armature 5 has been compressed at one axial end, removal of the disc 9 and thus the second closure part 7b from the interior of the armature 5 is no longer possible, since deformation of the axial end of the armature 5 prevents removal of the disc 9. Subsequently, the armature can be inserted together with the core 4 into the interior of the valve housing 10, and after the core 9 has been secured, the solenoid valve is ready for use.

[0047] The air movement in the individual switching positions occurs along the through-holes 13 and the outer grooves 14. For this purpose, one or more grooves 14 are provided along the outer cylindrical surface of the armature 5, which allow an axial air flow into or from the third port 3. The media flow (air) therefore runs from the first port 1 to the third port 3 through the core valve seat 12 and is guided through the transverse bore 13 in the armature 5. From the transverse bore 13 in the armature 5, the air flow continues via the aforementioned outer grooves to the third port 3.

[0048] An advantage of this air guide is that the outer grooves 14 of the armature 5 can already be present in the raw material and do not have to be manufactured separately. For example, this can be created using a turning process before the armature 5 is manufactured. This saves process time and therefore costs. The transverse bore 13 in the armature 5 enables air to be guided both from the inside to the outside and from the outside to the inside. Furthermore, the transverse bores 13, which serve to guide air between the first connection 1 and the third connection 3, can be identical in construction to the transverse bore 13b, which creates pressure equalization between the first closure part 7a and the second closure part 7b.

[0049] The features of the invention disclosed in the description, the claims and the figures may be essential for the realization of the invention both individually and in any combination.

[0050] LIST OF REFERENCE SYMBOLS

[0051] 1, 2, 3 connections

[0052] 4 cores 5 anchors

[0053] 5a, 5b, 5s, 5d sections from the anchor

[0054] 6 coil

[0055] 7, 7a, 7b, closure part(s)

[0056] 8 Damping spring 9 Disc

[0057] 10 housing body

[0058] 11 compression spring

[0059] 12 Valve seat (Kem)

[0060] 13, 13a, 13b Through openings 14 Side channel, groove

[0061] 15 chamber (interior)

[0062] 17a, 17b narrowed area (shoulder-head area / section)

Claims

PATENT CLAIMS 1. Solenoid valve with a first port (1), a second port (2), an armature (5) and a coil (6) for moving the armature (5), the solenoid valve is characterized by a first closing part (7a) which couples to the armature (5) and opens or closes the first port (1) upon movement of the armature (5); a second closing part (7b) which couples to the armature (5) and closes or opens the second port (2) upon movement of the armature (5); and a damping spring (8) which is arranged between the first closing part (7a) and the second closing part (7b) and is designed to cushion the closing of the first port (1) and / or the second port (2).

2. Solenoid valve according to claim 1, characterized in that only one damping spring (8) is arranged between the first closure part (7a) and the second closure part (7b), which pushes the first closure part (7a) and the second closure part (7b) away from each other.

3. Solenoid valve according to claim 1 or claim 2, characterized in that the first closure part (7a) is identical in construction to the second closure part (7b).

4. Solenoid valve according to one of the preceding claims, further comprising: a third port (3) and a chamber (15) in which the armature (5) together with the first and second closure part (7a, 7b) are linearly movable and the first, second and third ports (1, 2, 3) provide a connection to the chamber (15), characterized in that - in a current-energized state of the coil (6) the first sealing part (7a) closes the first terminal (1 ) and the second sealing part (7b) establishes a fluid connection via the chamber (15) between the second terminal (2) and the third terminal (3) and - in a de-energized state of the coil (6) the second sealing part (7b) closes the second terminal (2) and the first sealing part (7a) establishes a fluid connection via the chamber (15) between the first terminal (1) and the third terminal (3).

5. Solenoid valve according to one of the preceding claims, wherein the armature (5) extends cylindrically around the first closure part (7a) and around the second closure part (7b) and has a section (5a) projecting axially beyond the first closure part (7a) and a longitudinally extending side channel (14), characterized in that the armature (5) has at least two through-openings (13a, 13b) between an inner region of the armature (5) and the side channel (14), wherein a first through-opening (13a) is formed in the projecting section (5a) and a second through-opening (13b) is formed in a region (5b) of the armature (5) axially between the first closure part (7a) and the second closure part (7b) in order to provide pressure equalization between the inner region and an outer region of the cylindrical armature (5).

6. Solenoid valve according to claim 5, characterized in that the at least two through-openings (13) are identical bores.

7. Solenoid valve according to claim 5 or claim 6, characterized in that - the first and second closure part (7a, 7b) each have a head-shoulder area (17a, 17b) for closing the associated first or second connection (1, 2), - the anchor (5) has a radially projecting projection (5c) into the interior and at an opposite end an annular recess (5d) with a stop element (9), wherein the projection (5c) is designed to form a stop for the head-shoulder region (17a) of the first locking part (7a) and the recess (5d) is designed to allow, after insertion of the first locking part (7a), the damping spring (8) and the second The locking part (7b) is used to fix the second locking part (7b) in the axial direction via the stop element (9).

8. Solenoid valve according to claim 7, characterized in that the stop element (9) is a disc (9) which is fixed within the recess (5d) by an edge compression of the armature (5).

9. Method for manufacturing a solenoid valve, wherein the solenoid valve has a first port (1), a second port (2), an armature (5) with a cylindrical interior and a coil (6) for moving the armature (5) and the method is characterized by: - Inserting (S110) a first locking part (7a) into the interior of the anchor (5); - Inserting (S120) a damping spring (8) into the interior of the anchor (5); and - Insertion (S130) of a second locking part (7b) into the interior of the anchor (5), wherein the first locking part (7a) and the second locking part (7b) are designed to alternately open or close the first port (1) or the second port (2) when the anchor moves, while the damping spring (8) provides damping when closing the first port (1) and / or the second port (2).

10. The method of claim 9, characterized in that the method further comprises: Forming (S135) a stop for the second locking part (7b) by edge compression of the anchor (5) to ensure that the first locking part (7a), the second locking part (7b) and damping springs (8) arranged between them are fixed within the cylindrical cavity of the anchor (5).

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